Dyes derived from aminotrisazo compounds.



UNITED STATES PATENT onrica.

AUGUST BLANK AND MATTEIAS LATTEN, OE LEVERKUSEN, Hm COLOGNE, Gm"

MANY, ASSIGNOBS T0 FABBENFABRIKEN VORM. FRIEDB. BAYER & ('10., OF ELBEBFELD, GERMANY, A CORPORATION OF GEREANY.

Specification of Letterslatent.

DYES DERIVED FROM AMINO-TBISAZO COMPOUNDS.

Patented Feb. 17, 1am.

Application filed March 25, 1918. Serial No. 7 56,710.

the-Rhine, Germany, have invented new and useful Improvements in Dyes Derived'from Aminotrisazo Compounds, of which the following is a specification.

Our invention relates to the manufacture and production of new azo dyestufls capable of dyeing unmordanted cotton in brown shades distinguished by their excellent fastness to light. 7

The process for their production consists in converting aminotrisazo compounds containing an acid group, such as sulfonic or carboxylic acids and which contain only an amino group but no free hydroxy group, into symmetrical diarylurea compounds by treatment with phosgen.- The new dyes are after being dried and pulverized brownish powders soluble in cold water generally with a brown and in concentrated sulfuric acid with a greenish-blue coloration. Upon reduction with stannous chlorid and hydrochloric acid the corresponding amins, diamins one of which contains an acid group and carbonic acid, are obtained.

' To illustrate our process, we can proceed as follows, the parts being by weight :-59.3

parts of the aminotrisazo product, obtained by combining diazotized aminoazobenzenedisulfonic acid with meta-'toluidin, then diazotizing the product thus obtained and combining it with a second molecule of metatoluidin, are dissolved in 1380 parts of water and the necessary quantity of sodium carbonate. After the addition of 13.8 parts of soda phosgen is introduced into this solution which has to be stirred and kept alkaline until the production of the urea is complete. The new coloring matter is filtered ofi' and dried. It is after being dried and pulverized a brownish powder soluble in water with a yellowish-brown and in concentrated sulfuric acid (66 B.) with a greenish-blue coloration. When ice or cold water is added to it the greenish-blue solution changes to brownish-red. A brownishred precipitate being obtained. The dye yields upon reduction with stannous chlorid and hydrochloric acid para-sulfanilic acid, phenylenediamin-sulfonic acid, 1.3.6-tolulylenediamin and carbonic acid. It has most probably the formula:

(SOgH- N-N- soar which is after being dried and pulverized a brownto brownish-red powder soluble in water with a yellowish-brown and in conl C I trisazo compounds, which dyes are after being dried and pulverized brownish powders.

soluble in water with aI'brown and in concentrated sulfuric acid with a eenish-blue coloration; yielding upon re uction with stannous chlorid and hydrochloric acid generally the corresponding amins, diamins one of which contains an acid group and carbonic acid; dyeing cotton directly in brown shades distinguished by their excellent fastne'ss to light, substantially as described.

2. The herein described new azo dye having most probably the formula:

on. (in; centrated sulfuric acid (66- B.) with a greenish-blue coloration, which changes to brownish-red when ice or cold water is addmom-as ed to this solution and insoluble in cold concentrated soda lye; yielding upon reduotion with stannous chlorid and hydrochloric acid para-sulfanilic acid, parahenylenediamin-sulfonic acid, 1.3.6-t0lu enediamin and CO and dyeing cotton d:- r'ectly in brown shades, substantially as described.

In testiinony whereof we have hereunto AUGUST BLANK.

MATTHIAS LATTEN. "Witnesses HELEN NUFER, ALBERT NUFER. 

